TRUNCATE quickly removes all rows from a table. It has the same effect as an unqualified DELETE but since it does not actually scan the table it is faster. This is most useful on large tables.
Only the owner of a table may TRUNCATE it.
TRUNCATE cannot be used if there are foreign-key references to the table from other tables. Checking validity in such cases would require table scans, and the whole point is not to do one.
TRUNCATE will not run any user-defined ON DELETE triggers that might exist for the table.
If you do not own the target table then you can not TRUNCATE said table.
TESTDB=> TRUNCATE TABLE tbl_test;
ERROR: must be owner of relation tbl_test